Fig. 1.-Clear rim around plagioclase in contact with K-feldspar

A---Inclusions of plagioclase (Pl₁, Pl₂, Pl₃) are contained in K-feldspar (K₁). Albite rim (Ab ₂single prime,
Ab ₃single prime) occurs at contacts around plagioclase inclusions (Pl₂, Pl₃ oriented differently with K-feldspar) but are absent along the border of plagioclase inclusion (Pl₁ co-oriented with K₁). The growth of albite Ab ₂single prime is blocked where contacts occur with another plagioclase of perthitic albite. Naqin granite, Taishan County, Guangdong Province.

B---Albite rim (Ab ₁ single prime ) is present only at the contact of plagioclase Pl₁ with K-feldspar. The plagioclase is not sericitized.

C---Albite rim is absent at contact with quartz.

D---Replacive albite occurs at the border of plagioclase with K-feldspar.

E---Relicts of perthitic albite remain in the clear rim Ab’, indicating the replacement origin of the latter.

F---Arrows show the growth direction of the replacive albite.